Approach to the yellow patient

What are common clinical signs of jaundice in a horse?

• mild, recurrent colic

• jaundice - yellow tissues

• lethargy

• photosensitisation

• weight loss - chronic

• neurological changes

• fever

what neurological changes may we see with horses with jaundice

• head pressing

• circling

• abnormal behaviour

what is the aetiology of jaundice?

• anorexia

• haemolytic disease - e.g. neonatal isoerythrolysis

• hepatobiliary causes - inflamation of liver/biliary tract

common differentials of jaundice in horses?

• infectious cause

• bilary obstruction

• ragwort poisoning

what are diagnostic options and next steps for equine

1. biochemistry will show elevated GGT, AST, bile acids and increase bilirubin

2. SDH may be elevated

3. increased blood ammonia in cases of hepatic-encepalopathy

treatment of jaundice in horses?

• supportive therapy

• antimicrobials if bacterial origin

• difficult treatment once liver starts to fail

what may help diagnose liver conditions in equine with jaundice?

• ultrasound - hepatomegaly and distended bile duct. May see cholethiths

• liver biopsy

in which farm species do we see jaundice

• pregnant texel sheep

is jaundice common farm animals?

• no

common presenting history + clinical signs of farm animals

• adult pregnant texel ewes

• housed in loose straw yards

• hay and brewer’s grains

• yellow mucous membranes, aimless wandering, head pressing, dark coloured urine.

is there good prognosis once neurological signs are seen in jaundice sheep

• nope

aetiology and pathogenesis of farm animals

• increased Cu intake from diet/environment

• crisis

  • haemolytic anaemia

what are some sources of increased Cu in sheep?

• diet - forage/brewer’s grains, incorrect concentrates

• foodbath, pesticides, industrial waste in water, pig slurry, poultry filter

how do we get haemolytic anaemia

• liver damage, RBC destruction.

• Liver storage exceeded → sudden release into blood.

common differentials for jaundice in sheep

• copper toxicity

• eperythrozoonosis - mycoplasma ovis

• mycotoxins

diagnostic options and next steps for jaundice in farm animals

Definitive: PME (post mortem), pale liver, black kidneys → liver copper concentrations

• consider history

treatment options for jaundice farm animals

1. 3 doses of ammonium tetrethiomolybdate

2. addition of Cu antagonists to diet

consider whether animal is worth treating - those showing neurological signs often are too far gone

what should farmers avoid using to reduce risk of icterus?

• avoid using high Cu concentrates

• have veterinary advice on what copper supplements should be given

Common presenting signs of a yellow tortoise

1. yellow mucous membranes - sometimes cheeks+gums with pink tongue, sometimes tongue is also yellow

2. may seem more lethargic, anorexic and experience weight loss

3. may be completely normal otherwise

what is the aetiology and pathogenesis of jaundice in tortoises?

• liver disease - frequently caused by poor diet

  • infections/cirrhosis

• some ectoparasites → secodnary bacterial infections

state the common differentials for jaundice in tortoises

1. stomatitis/mouth rot

2. herpes virus

3. poor diet/hypovitaminosis A

4. dandelions

5. over supplementation post-hibernation jaundice

6. liver disease

7. Hexamita parva

8. hepatic lipidosis infection

state 2 causes of hepatic lipidosis infection disease in tortoises

1. salmonella spp.

2. Aeromonas hydrophila

what diagnostic options and next steps do we want to take for a yellow tortoise

1. examine diet

2. haematology + biochemistry - liver enzymes are less reliable

3. faecal testing - endoparasites

4. cytology - infection

5. virus testing (open mouth swab for herpes)

treatment of a yellow tortoise?

1. correct diet and supplements

2. keep at 30 degrees celcius

3. oesophagostomy tube if anorexic/needs oral medication

4. other treatment depends on cause - e.g. bacterial or viral or endoparasites etc.

common clinical signs of a yellow dog

1. yellow mucous membranes

2. dark urine

others

1. lethargy

2. vomit/diarrhoea

3. PU/PD

4. weight loss

5. abdominal pain/distension

6. pyrexia

7. neurological signs

in dogs, if jaundice is pre-hepatic, what does this mean

1. increased RBC destruction

in dogs, if jaundice is hepatic what does this mean

• functional liver disease - unable to conjugate bilirubiin so can’t excrete into biliary system

what does it mean in dogs if the jaundice is post-hepatic

• destruction of biliary system.

  • unconjugated bilirubin can’t be excreted

common differentials for prehepatic jaundice

• IMHA

• toxicity - onion/zinc

• RBC parasites (babesia)

common differentials for hepatic jaundice

• hepatic neoplasia

• toxicity

• leptospirosis

• acute/chronic hepatopathy/cirrhosis

common differentials for post hepatic jaundice

• neoplasia

• gall bladder stones/mucocoele

• pancreatitis

diagnostic options and next steps for a jaundice dog

1. history and clinical exam (maybe faeces to rule out fluke)

2. biochemistry, haematology, PCV, blood smear, bile acid stimulation test - bloods

3. urinalysis - dipstick, USG, microscopy

4. abdominal ultrasound

treatment options for a jaundice dog

depends on cause:

• fluid therapy, transfusion, analgesia, charcoal, steroids/immunosuppressants, antibiotics, surgery, dietary changes…….